Search results for: pressure reducing valve

Authors: Maria Konstadinou, Etienne Alderlieste, Anderson Peccin da Silva, Ben Arntz, Leonard van der Bijl, Wouter Verschueren

Abstract:

The shear strength and compression properties of stiff Boom clay from Belgium at the depth of about 30 m has been investigated by means of cone penetration and laboratory testing. The latter consisted of index classification, constant rate of strain, direct, simple shear, and unconfined compression tests. The Boom clay samples exhibited strong swelling tendencies. The suction pressure was measured via different procedures and has been compared to the expected in-situ stress. The undrained shear strength and OCR profile determined from CPTs is not compatible with the experimental measurements, which gave significantly lower values. The observed response can be attributed to the presence of pre-existing discontinuities, as shown in microscale CT scans of the samples. The results of this study demonstrate that the microstructure of the clay prior to testing has an impact on the mechanical behaviour and can cause inconsistencies in the comparison of the laboratory test results with in-situ data.

Keywords: boom clay, laboratory testing, overconsolidation ratio, stress-strain response, swelling, undrained shear strength

Procedia PDF Downloads 138

Authors: Muhammad Saad Shoaib Khan, Rasbin Basnet, Qingyao Shu

Abstract:

Phospholipids are one of the major classes of lipid comprising 10% of total grain lipid in rice. Phospholipids are the main phosphorus containing lipid in the rice endosperm, contributing to rice palatability and seed storage property. However, in the rice grain, the majority of phosphorus occur in the form of phytic acid and are highly abundant in the bran. Phytic acid, also known as hexaphosphorylated inositol (IP6), are strong chelating agents which reduces the bioavailability of essential dietary nutrients and are therefore less desirable by rice breeders. We used the CRISPR/Cas9 system to generate mutants of a phospholipase D gene (PLDα1), which is responsible for the degradation of phospholipids into phosphatidic acid (PA). In the mutants, we found a significant reduction in the concentration of phytic acid in the grain as compared to the wild-type. The biochemical analysis of the PLDα1 mutants showed that the decrease in production of phosphatidic acid is due to reduced accumulation of CDP-diacylglycerolderived phosphatidylinositol (PI), ultimately leading to lower accumulation of phytic acid in mutants. These results showed that loss of function of PLD in rice leads to lower production of phytic acid, suggesting the potential application of Ospldα1 in breeding rice with less phytic acid.

Keywords: CRISPR/Cas9, phospholipase D, phytic acid, rice

Procedia PDF Downloads 150

Authors: Andrew D. Henshaw

Abstract:

The research examines the influence of familial and kinship based leadership on the resilience of politically violent organizations. Organizations of this type frequently fight in the same conflicts though are called 'terrorist' or 'insurgent' depending on political foci of the time, and thus different approaches are used to combat them. The research considers them correlated phenomena with significant overlap and identifies strengths and vulnerabilities in resilience processes. The research employs paired case studies to examine resilience in organizations under significant external pressure, and achieves this by measuring three variables. 1: Organizational robustness in terms of leadership and governance. 2. Bounce-back response efficiency to external pressures and adaptation to endogenous and exogenous shock. 3. Perpetuity of operational and attack capability, and political legitimacy. The research makes three hypotheses. First, familial/kinship leadership groups have a significant effect on organizational resilience in terms of informal operations. Second, non-familial/kinship organizations suffer in terms of heightened security transaction costs and social economics surrounding recruitment, retention, and replacement. Third, resilience in non-familial organizations likely stems from critical external supports like state sponsorship or powerful patrons, rather than organic resilience dynamics. The case studies pair familial organizations with non-familial organizations. Set 1: The Haqqani Network (HQN) - Pair: Lashkar-e-Toiba (LeT). Set 2: Jemaah Islamiyah (JI) - Pair: The Abu Sayyaf Group (ASG). Case studies were selected based on three requirements, being: contrasting governance types, exposure to significant external pressures and, geographical similarity. The case study sets were examined over 24 months following periods of significantly heightened operational activities. This enabled empirical measurement of the variables as substantial external pressures came into force. The rationale for the research is obvious. Nearly all organizations have some nexus of familial interconnectedness. Examining familial leadership networks does not provide further understanding of how terrorism and insurgency originate, however, the central focus of the research does address how they persist. The sparse attention to this in existing literature presents an unexplored yet important area of security studies. Furthermore, social capital in familial systems is largely automatic and organic, given at birth or through kinship. It reduces security vetting cost for recruits, fighters and supporters which lowers liabilities and entry costs, while raising organizational efficiency and exit costs. Better understanding of these process is needed to exploit strengths into weaknesses. Outcomes and implications of the research have critical relevance to future operational policy development. Increased clarity of internal trust dynamics, social capital and power flows are essential to fracturing and manipulating kinship nexus. This is highly valuable to external pressure mechanisms such as counter-terrorism, counterinsurgency, and strategic intelligence methods to penetrate, manipulate, degrade or destroy the resilience of politically violent organizations.

Keywords: Counterinsurgency (COIN), counter-terrorism, familial influence, insurgency, intelligence, kinship, resilience, terrorism

Procedia PDF Downloads 305

Authors: Marlene Kuhn, Franziska Schäfer, Heiner Otten

Abstract:

Today´s production processes experience a constant increase in complexity paving new ways for progressive forms of leadership. In the customized production, individual customer requirements drive companies to adapt their manufacturing processes constantly while the pressure for smaller lot sizes, lower costs and faster lead times grows simultaneously. When production processes are becoming more dynamic and complex, the conventional quality management approaches show certain limitations. This paper gives an introduction to complexity science from a quality management perspective. By analyzing and evaluating different characteristics of complexity, the critical complexity parameters are identified and assessed. We found that the quality of leadership plays a crucial role when dealing with increasing complexity. Therefore, we developed a concept for qualitative leadership customized for the management within complex processes based on a maturity model. The maturity model was then applied in the industry to assess the leadership quality of several shop floor managers with a positive evaluation feedback. In result, the maturity model proved to be a sustainable approach to leverage the rising complexity in production processes more effectively.

Keywords: maturity model, process complexity, quality of leadership, quality management

Procedia PDF Downloads 361

Authors: Mohammed Bakhit Kashoob, Mohammed Salim Al-Maashani, Ahmed Abdullah Al-Marhoon

Abstract:

Traffic calming measures are different design features or strategies used to reduce the speed of a traveling vehicle on a particular road. These calming measures are common on rural roads of Oman. Some of these measures are road speed limits, vertical deflections, horizontal deflections, and road signs. In general, vertical deflections such as rumble strips, road studs (cat’s eye), speed tables, and speed humps are widely used. In this paper, as vehicle speeding is a major cause of road traffic crashes and high fatalities in Oman, the effectiveness of existing traffic calming measures at current locations on rural roads is assessed. The study was conducted on the rural roads of Dhofar Governorate, which is located in the south of Oman. A special focus is given to the calming measures implemented on the mountain roads of Dhofar. It is shown that vertical deflection calming measures are effective in reducing vehicle speed to 20 to 40 kph, depending on the vertical deflection type and spacing. Calming measures are also proposed at locations with a high probability of traffic crashes based on the number of traffic crashes at these locations, road type, and road geometry.

Keywords: road safety, rural roads, speed, traffic calming measures, traffic crash

Procedia PDF Downloads 107

Authors: Wen-Chen Hwang, Yu-Hsi Yuan

Abstract:

According to the estimation made by researchers of safety and hygiene, 80% to 90% of workplace accidents in enterprises could be attributed to human factors. Nevertheless, human factors are not the only cause for accidents; instead, happening of accidents is also closely associated with the safety culture of the organization. Therefore, the most effective way of reducing accident rate would be to improve the social and the organizational factors that influence organization’s safety performance. Overview the present study is to understand the current level of safety culture in manufacturing enterprises. A tool for evaluating safety culture matching the needs and characteristics of manufacturing enterprises was developed by reviewing literature of safety culture, and taking the special backgrounds of the case enterprises into consideration. Expert validity was also implied for developing the questionnaire. Moreover, safety culture assessment was conducted through the practical investigation of the case enterprises. Total 505 samples were involved, 53 were executives and 452 were operators. The result of this study in comparison of the safety culture level between the executives and the operators was reached the significant level in 8 dimensions: Safety Commitment, Safety System, Safety Training, Safety Involvement, Reward and Motivation, Communication and Reporting, Leadership and Supervision, Learning and Changing. In general, the overall safety culture were executive level higher than operators level (M: 74.98 > 69.08; t=2.87; p < 0.01).

Keywords: questionnaire survey, safety culture, t-test, media studies

Procedia PDF Downloads 308

Authors: Hamidreza Ahmadi, Majid Abbasalizadeh, Ghasem Yazdani, Masoud Ahmadi

Abstract:

In this paper a special kind of aerodynamic system as a spoiler has been designed and tried to show effects of this devise on braking system of vehicle. Moreover, position of this spoiler has been considered in order to find optimum point from safety and highest rate of braking view for spoiler. Fluent software is our main tool to calculate rate of extra force that is produced by spoiler and this article has been tried to use various figures that are showed effects of spoiler at different speeds, angles and also heights. Other major points in this paper are static pressure of vehicle at different speed and statues. Undoubtedly, shape of spoiler would be very important, so in this investigation spoiler has been designed and proposed after a lot of simulation for different shape of spoiler. In the end, there is very important part as validation since these simulations must be validated by experimental way to prove our claims. In this case, a special kind of BMW has been simulated and results have been compared by experimental results that have been presented by BMW Company. Difference between simulation results and experimental results are very little and it could be a suitable validation for this project.

Keywords: drag force, down force, vehicle, spoiler

Procedia PDF Downloads 326

Authors: R. Ramesh, M. Y. M. Yunus, K. Ramesh

Abstract:

The study conducted in this research are Viscosities, η, and Densities ,ρ, of 1, 4-dioxane with Bromobenzene at different mole fractions and various temperatures in the atmospheric pressure condition. From experimentations excess volumes, VE, and deviations in viscosities, Δη, of mixtures at infinite dilutions have been obtained. The measured systems exhibited positive values of VmE and negative values of Δη. The binary mixture 1, 4 dioxane + Bromobenzene show positive VE and negative Δη with increasing temperatures. The outcomes clearly indicate that weak interactions present in mixture. It is mainly because of number and position of methyl groups exist in these aromatic hydrocarbons. These measured data tailored to the nonlinear models to derive the binary coefficients. Standard deviations have been considered between the fitted outcomes and the calculated data is helpful deliberate mixing behavior of the binary mixtures. It can conclude that in our cases, the data found with the values correlated by the corresponding models very well. The molecular interactions existing between the components and comparison of liquid mixtures were also discussed.

Keywords: 1, 4 dioxane, bromobenzene, density, excess molar volume

Procedia PDF Downloads 402

Authors: Hamidreza Bagheri, Alireza Shariati

Abstract:

There are many difficulties in the purification of raw components and products. However, researchers are seeking better ways for purification. One of the recent methods is extraction using supercritical fluids. In this study, the phase equilibria of benzoic acid-supercritical carbon dioxide system were investigated. Regarding the phase equilibria of this system, the modeling of solid-supercritical fluid behavior was performed using the Perturbed-Chain Statistical Association Fluid Theory (PC-SAFT) and Peng-Robinson equations of state (PR EoS). For this purpose, five PC-SAFT EoS parameters for pure benzoic acid were obtained using its experimental vapor pressure. Benzoic acid has association sites and the behavior of the benzoic acid-supercritical fluid system was well-predicted using both equations of state, while the binary interaction parameter values for PR EoS were negative. Genetic algorithm, which is one of the most accurate global optimization algorithms, was also used to optimize the pure benzoic acid parameters and the binary interaction parameters. The AAD% value for the PC-SAFT EoS, were 0.22 for the carbon dioxide-benzoic acid system.

Keywords: supercritical fluids, solubility, solid, PC-SAFT EoS, genetic algorithm

Procedia PDF Downloads 511

Authors: Feng Zhang, Li Chen, Desong Kong, Xiaoping Zhang, Xiaojing Zhu, Yin Lu, Shizhong Zheng

Abstract:

Sinusoidal pathological angiogenesis is a novel therapeutic target for liver fibrosis. We demonstrated that curcumin ameliorated fibrotic injury and sinusoidal angiogenesis in rat liver with fibrosis caused by carbon tetrachloride. Curcumin reduced the expression of angiogenic markers in fibrotic liver. Experiments in vitro showed that the viability and vascularization of rat liver sinusoidal endothelial cells (LSECs) were not impaired by curcumin. Further investigations showed that curcumin inhibited VEGF expression in hepatic stellate cells (HSCs) by disrupting PDGF-βR/ERK and mTOR pathways. HSC motility and vascularization were also suppressed by curcumin via blocking PDGF-βR/FAK/RhoA cascade. Gain- or loss-of-function analyses revealed that activation of PPARγ was required for curcumin to inhibit angiogenic properties of HSCs. We concluded that curcumin attenuated sinusoidal angiogenesis in liver fibrosis possibly by targeting HSCs via a PPARγ activation-dependent mechanism. PPARγ could be a target molecule for reducing pathological angiogenesis during liver fibrosis.

Keywords: angiogenesis, hepatic stellate cell, curcumin, peroxisome proliferator-activated receptor-γ

Procedia PDF Downloads 507

Authors: Mariam Arif

Abstract:

The objective of the current study is to find out the electoral violence against women and its implications on their political participation. This paper is a qualitative study to get an in-depth analysis of the phenomenon. This study used questionnaires and interviews for findings. This paper attempts to study electoral violence and women in politics in Pakistan. The study concluded that women are subjected to different categories of violence defined as physical violence that involves sexual and bodily harm to a politically active woman or to people associated with her. Social and psychological violence includes class difference, stress, social limitations, family pressure and character assassination. Economic violence is defined as a systematic restriction of access to economic resources available to women thus hinder women active participation in politics (elections). All these violence against women in elections are threat to the integrity of the electoral process of the country that eventually affects women’s participation as voters, party candidates, election officials and political party leaders. It also undermines the free and fair democratic process. This qualitative paper shows a significant negative relationship between electoral violence and women participation in politics.

Keywords: elections, politics, violence, women

Procedia PDF Downloads 155

Authors: Bin Li

Abstract:

In the era of the digital economy, digital transformation has gradually become a strategic choice for enterprise development, but there is a relative lack of systematic research from the perspective of enterprise growth. Based on the sample of Chinese A-share listed companies from 2011 to 2021, this paper constructs A digital transformation index system and an enterprise growth composite index to empirically test the impact of enterprise digital transformation on enterprise growth and its mechanism. The results show that digital transformation can significantly promote corporate growth. The mechanism analysis finds that reducing operating costs, optimizing human capital structure, promoting R&D output and improving digital innovation capability play an important intermediary role in the process of digital transformation promoting corporate growth. At the same time, the level of external digital infrastructure and the strength of organizational resilience play a positive moderating role in the process of corporate digital transformation promoting corporate growth. In addition, while further analyzing the heterogeneity of enterprises, this paper further deepens the analysis of the driving factors and digital technology support of digital transformation, as well as the three dimensions of enterprise growth, thus deepening the research depth of enterprise digital transformation.

Keywords: digital transformation, enterprise growth, digital technology, digital infrastructure, organization resilience, digital innovation

Procedia PDF Downloads 51

Authors: Radhika Ramanchi

Abstract:

The oil market during 2014-2015 in India with large price fluctuations is very confusing to individual investor. The drop in oil prices supported stocks of some oil marketing companies (OMCs) like Bharat Petroleum Corporation, Hindustan Petroleum Corporation (HPCL) and Indian Oil Corporation etc their shares rose 84.74%, 128.63% and 59.16%, respectively. Lower oil prices, and lower current account, a smaller subsidy burden are the reasons for outperformance. On the other hand, lower crude prices giving downward pressure on upstream companies like Oil and Natural Gas Corp. Ltd (ONGC) and Reliance Petroleum (RIL) Oil India Ltd (OIL). Not having clarity on a subsidy sharing mechanism is the reason for downward trend on these stocks. Shares of ONGC and RIL have underperformed so far in 2015. When the oil price fall profits of the companies will effect, generate less money and may cut their dividends in Long run. In this situation this paper objective is to study investment strategies in oil marketing companies, by applying CAPM and Security Market Line.

Keywords: petrol industry, price fluctuations, sharp single index model, SML, Markowitz model

Procedia PDF Downloads 215

Authors: D. Deepak, N. Yagnesh Sharma

Abstract:

Abrasive Water Jet (AWJ) machining is a relatively new nontraditional machine tool used in machining of fiber reinforced composite. The quality of machined surface depends on jet exit kinetic energy which depends on various operating and material parameters. In the present work the effect abrasive parameters such as its size, concentration and type on jet kinetic energy is investigated using computational fluid dynamics (CFD). In addition, the effect of these parameters on wall shear stress developed inside the nozzle is also investigated. It is found that for the same operating parameters, increase in the abrasive volume fraction (concentration) results in significant decrease in the wall shear stress as well as the jet exit kinetic energy. Increase in the abrasive particle size results in marginal decrease in the jet exit kinetic energy. Numerical simulation also indicates that garnet abrasives produce better jet exit kinetic energy than aluminium oxide and silicon carbide.

Keywords: abrasive water jet machining, jet kinetic energy, operating pressure, wall shear stress, Garnet abrasive

Procedia PDF Downloads 373

Authors: Mahmoud Enayati, Sirous Mohammadi

Abstract:

In this paper, a novel procedure to find the firing angles of the multilevel inverters of supply voltage and, consequently, to decline the total harmonic distortion (THD), has been presented. In order to eliminate more harmonics in the multilevel inverters, its number of levels can be lessened or pulse width modulation waveform, in which more than one switching occur in each level, be used. Both cases complicate the non-algebraic equations and their solution cannot be performed by the conventional methods for the numerical solution of nonlinear equations such as Newton-Raphson method. In this paper, Cuckoo algorithm is used to compute the optimal firing angle of the pulse width modulation voltage waveform in the multilevel inverter. These angles should be calculated in such a way that the voltage amplitude of the fundamental frequency be generated while the total harmonic distortion of the output voltage be small. The simulation and theoretical results for the 9-levels inverter offer the high applicability of the proposed algorithm to identify the suitable firing angles for declining the low order harmonics and generate a waveform whose total harmonic distortion is very small and it is almost a sinusoidal waveform.

Keywords: evolutionary algorithms, multilevel inverters, total harmonic content, Cuckoo Algorithm

Procedia PDF Downloads 529

Authors: A. Basheer Ahamadhu, Kiran Kaur, Zainab Ajab Mohideen, Sukmawati Muhammad, Noor Azlinda Wan Jan

Abstract:

Library management facing favorable conditions and unexpected challenges in the century of information technology. They were having been under pressure to meet their duties to meet the information needs of customers. An information technology has brought big changes to the traditional methods of library work. Libraries need to evaluate, measuring effect information technology to them. This would equip them with the knowledge to make effective information technology to enhance their services. Recognizing the importance of development an electronic library, this research investigated their willingness to change from the traditional library based on the level of automation for the digital library initiatives, review both of the problems associated with digital library and public and terms to be considered for future growth. The main components have been inspected, such as grip library, demographic automations and digitization projects, digital library related to budgetary problems, the thought leader in the electronic library practices library, and the situation viewed for future growth. Libraries have run several digitization projects, at the level of institutions and countries but still needs more efforts in order to bring it to higher levels.

Keywords: academic library, electronic library, information technology, information commons, web pages library

Procedia PDF Downloads 466

Authors: Oluwatosin Oyewale

Abstract:

This research work seeks to take technology used for business systems as a product that requires marketing activities. Technology is invented and innovated upon in developed countries and are introduced into Africa through marketing activities. Businesses in Africa now adopt this technology for global competitiveness and hitherto unemployed but educationally advantaged people are trained in handling and utilising the technology. The aim of this study is to examine how marketing activities make this technology help in solving the unemployment problem in Africa. The areas of study are both the premier local government and the local government of the industrial haven in Ogun State, Nigeria. Area or cluster sampling technique was employed and Questionnaires were administered to two hundred respondents in the areas of study. Findings revealed that marketing has contributed to the promotion of technology; thereby making businesses globally competitive. In addition, technology has helped in reducing unemployment in developing countries. Recommendations are that training programmes that will address existing knowledge gap in technology utilisation needs to be conducted for the labour force in Africa. Moreover, adequate power supply that will aid effective utilisation of these technologies needs to be put in place by the government in these various African countries.

Keywords: marketing, unemployment, problem, panacea

Procedia PDF Downloads 216

Authors: Abdulrahman H. Alrashidi

Abstract:

Kuwait Oil Company provides health care services through Ahmadi hospital for oil sector employee and their families. Due to increasing number of entitled patients in Ahmadi hospital, the company starts health insurance option in 2010. In addition, a new Ahmadi hospital decided to build to accumulate all entitled patients. Operation and management of new Ahmadi hospital investigated in this research. In order to maintain the high quality of medical services and satisfaction rate among oil sector community and reducing the operation cost. Six operation and management options evaluated in order to implement in new Ahmadi hospital. Qualitative Risk assessment method used to investigate proposed options for operation and management of new Ahmadi hospital. Evaluation criteria consist of quality of medical services, operation cost and satisfaction rate among oil sector community. Results show that using the same operation and management system in existing Ahmadi hospital with new Ahmadi hospital will bring cost higher. This approach brings risk to KOC. Results from risk assessment show that partially operated new Ahmadi hospital is the best opportunity to meet the objectives of KOC’s medical group.

Keywords: Kuwait Oil Company, new Ahmadi hospital, operation and management, risk assessment

Procedia PDF Downloads 353

Authors: Priyadarshini Alok

Abstract:

The present situation in India envisages that because of the surge in population and the economy, cities are expected to spill over to hinterland areas. The consumption-led factors such as land, labor, etc. will be boosted. Hence, the need for regional connectivity becomes obligatory. But, there is enormous pressure upon the land; proving itself through rising traffic congestion, roads, and railway accidents. Air transport is practical, but due to decreasing availability of land, this will not be a wise solution. What with the introduction of seaplanes in the country which was once the vital asset in the world prior to Second World War. Maldives has proved it. Seaplanes offer natural landing site and are time and cost-efficient. Seaplanes in accordance with UDAN can prove to be the solution in linking various regions with other states. This research paper aims to offer the feasibility analysis along with site justification of the potential areas in the state of Andhra Pradesh, India; for the operation of seaplanes. The standards are taken from the US Department of Transportation, Federal Aviation Administration for the analysis. The conflation of Seaplanes with UDAN will offer an alternate mode of air connectivity, strengthen the transport network by simulation of connectivity to unserved and under-served areas and boost the nation's economy.

Keywords: connectivity, seaplanes, transport, UDAN

Procedia PDF Downloads 165

Authors: N. Reza Pour, S. Chuah, T. Vo

Abstract:

Background: Vertebral artery dissection (VAD) is a rare complication of pregnancy. It can occur spontaneously or following a traumatic event. The pathogenesis is unclear. Predisposing factors include chronic hypertension, Marfan’s syndrome, fibromuscular dysplasia, vasculitis and cystic medial necrosis. Physiological changes of pregnancy have also been proposed as potential mechanisms of injury to the vessel wall. The clinical presentation varies and it can present as a headache, neck pain, diplopia, transient ischaemic attack, or an ischemic stroke. Isolated cases of VAD in pregnancy and puerperium have been reported in the literature. One case was found to have posterior circulation stroke as a result of bilateral VAD and labour was induced at 37 weeks gestation for preeclampsia. Another patient at 38 weeks with severe neck pain that persisted after induction for elevated blood pressure and arteriography showed right VAD postpartum. A single case of lethal VAD in pregnancy with subsequent massive subarachnoid haemorrhage has been reported which was confirmed by the autopsy. Case Presentation: We report two cases of vertebral artery dissection in pregnancy. The first patient was a 32-year-old primigravida presented at the 38th week of pregnancy with the onset of early labour and blood pressure (BP) of 130/70 on arrival. After 2 hours, the patient developed a severe headache with blurry vision and BP was 238/120. Despite treatment with an intravenous antihypertensive, she had eclamptic fit. Magnesium solfate was started and Emergency Caesarean Section was performed under the general anaesthesia. On the second day after the operation, she developed left-sided neck pain. Magnetic Resonance Imaging (MRI) angiography confirmed a short segment left vertebral artery dissection at the level of C3. The patient was treated with aspirin and remained stable without any neurological deficit. The second patient was a 33-year-old primigavida who was admitted to the hospital at 36 weeks gestation with BP of 155/105, constant headache and visual disturbances. She was medicated with an oral antihypertensive agent. On day 4, she complained of right-sided neck pain. MRI angiogram revealed a short segment dissection of the right vertebral artery at the C2-3 level. Pregnancy was terminated on the same day with emergency Caesarean Section and anticoagulation was started subsequently. Post-operative recovery was complicated by rectus sheath haematoma requiring evacuation. She was discharged home on Aspirin without any neurological sequelae. Conclusion: Because of collateral circulation, unilateral vertebral artery dissections may go unrecognized and may be more common than suspected. The outcome for most patients is benign, reflecting the adequacy of the collateral circulation in young patients. Spontaneous VAD is usually treated with anticoagulation or antiplatelet therapy for a minimum of 3-6 months to prevent future ischaemic events, allowing the dissection to heal on its own. We had two cases of VAD in the context of hypertensive disorders of pregnancy with an acceptable outcome. A high level of vigilance is required particularly with preeclamptic patients presenting with head/neck pain to allow an early diagnosis. This is as we hypothesize, early and aggressive management of vertebral artery dissection may potentially prevent further complications.

Keywords: eclampsia, preeclampsia, pregnancy, Vertebral Artery Dissection

Procedia PDF Downloads 270

Authors: Yuxin Wu, Yu-Shing Wang, Zitao Zhang

Abstract:

A high-speed and time-lapse S-wave velocity measurement system has been built up for S-wave tomography in sand. This system is based on bender elements and applied to model pile tests in a tailor-made pressurized chamber to monitor the shear wave velocity distribution during pile installation in sand. Tactile pressure sensors are used parallel together with bender elements to monitor the stress changes during the tests. Strain gages are used to monitor the shaft resistance and toe resistance of pile. Since the shear wave velocity (Vs) is determined by the shear modulus of sand and the shaft resistance of pile is also influenced by the shear modulus of sand around the pile, the purposes of this study are to time-lapse monitor the S-wave velocity distribution change at a certain horizontal section during pile installation and to correlate the S-wave velocity distribution and shaft resistance of pile in sand.

Keywords: bender element, pile, shaft resistance, shear wave velocity, tomography

Procedia PDF Downloads 421

Authors: Mahdi Almaky, Reda Hassanin, Benjamin Horrocks, Andrew Houlton

Abstract:

DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires were synthesised at room temperature using the chemical oxidation method. The resulting CPs/DNA hybrids have been characterised using electronic and vibrational spectroscopic methods especially Ultraviolet-Visible (UV-Vis) spectroscopy and FTIR spectroscpy. The nanowires morphology was characterised using Atomic Force Microscopy (AFM). The electrical properties of the prepared nanowires were characterised using Electrostatic Force Microscopy (EFM), and measured using conductive AFM (c-AFM) and two terminal I/V technique, where the temperature dependence of the conductivity was probed. The conductivities of the prepared CPs/DNA nanowires are generally lower than PPy/DNA nanowires showingthe large effect on N-alkylation in decreasing the conductivity of the polymer, butthese are higher than the conductivity of their corresponding bulk films.This enhancement in conductivity could be attributed to the ordering of the polymer chains on DNA during the templating process. The prepared CPs/DNA nanowires were used as templates for the growth of copper nanowires at room temperature using aqueous solution of Cu(NO3)2as a source of Cu2+ and ascorbic acid as reducing agent. AFM images showed that these nanowires were uniform and continuous compared to copper nanowires prepared using the templating method directly onto DNA. Electrical characterization of the nanowires by c AFM revealed slight improvement in conductivity of these nanowires (Cu-CPs/DNA) compared to CPs/DNA nanowires before metallisation.

Keywords: templating, copper nanowires, polymer/DNA hybrid, chemical oxidation method

Procedia PDF Downloads 356

Authors: Eddegdag Nasser, Naamane Azzeddine, Radouani Mohammed, Ensam Meknes

Abstract:

In this study, we are interested in the asymptotic modeling of the two-dimensional stationary supersonic flow of a viscous compressible fluid around wing airfoil. The aim of this article is to solve the partial differential equations of the flow far from the leading edge and near the wall using the triple-deck technique is what brought again in precision according to the principle of least degeneration. In order to validate our theoretical model, these obtained results will be compared with the experimental results. The comparison of the results of our model with experimentation has shown that they are quantitatively acceptable compared to the obtained experimental results. The experimental study was conducted using the AF300 supersonic wind tunnel and a NACA Reduced airfoil model with two pressure Taps on extrados. In this experiment, we have considered the incident upstream supersonic Mach number over a dissymmetric NACA airfoil wing. The validation and the accuracy of the results support our model.

Keywords: supersonic, viscous, triple deck technique, asymptotic methods, AF300 supersonic wind tunnel, reduced airfoil model

Procedia PDF Downloads 231

Authors: Eliziane Navarro

Abstract:

It is intended, in this study, from some poems from the work of the poet and Bishop of Sao Felix do Araguaia-MT Brazil Dom Pedro Casaldaliga, to analyze his poetics from the perspective of the environmental law. In his work, Casaldaliga made a considerable manifest against the oppression experienced especially by Xavante people inside the countryside of the state of Mato Grosso when some government programs benefited a large number of landowners in instead of that minority as a power and control self-affirmation process. The attention which Casaldaliga dismissed to the cause of indigenous eviction of their land called Maraiwatsede resulted in numerous death threats against the poet who was not silenced in the face of the landowners’ grievances. His voice contributed significantly to the process of land returning to the indigenous people. Because of the international pressure, the Italian company AGIP, owner of the land, tried to return it to the hands of the indigenous, unfortunately, in the middle of the process, the land was occupied by politicians and big landowners of the region. Another objective of this research is to check the connection of his testimonial literature with the actual legal context of the state in the 50s and also to analyze his poetry as a complaint that led the cause of the state's indigenous to the Eco 92 discussion in Rio de Janeiro.

Keywords: law and literature, indigenous migration, Mato Grosso, Pedro Casaldaliga

Procedia PDF Downloads 237

Authors: Mehrdad Ebrahimi, Oliver Schmitz, Axel Schmidt, Peter Czermak

Abstract:

“Produced water” (PW) is any fossil water that is brought to the surface along with crude oil or natural gas. By far, PW is the largest waste stream by volume associated with oil and gas production operations. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging PW on the environment has lately become a significant issue of environmental concerns. Therefore, there is a need for new technologies for PW treatment due to increase focus on water conservation and environmental regulation. The use of membrane processes for treatment of PW has several advantages over many of the traditional separation techniques. In oilfield produced water treatment with ceramic membranes, process efficiency is characterized by the specific permeate flux and by the oil separation performance. Apart from the membrane properties, the permeate flux during filtration of oily wastewaters is known to be strongly dependent on the constituents of the feed solution, as well as on process conditions, e.g. trans-membrane pressure (TMP) and cross-flow velocity (CFV). The research project presented in these report describes the application of different ceramic membrane filtration technologies for the efficient treatment of oil-field produced water and different model oily solutions.

Keywords: ceramic membrane, membrane fouling, oil rejection, produced water treatment

Procedia PDF Downloads 174

Authors: Maha Ibrahim Mohamed Khalifa

Abstract:

Background: Dental fear and anxiety lead to avoidance of dental treatment and deterioration of oral health. Aim of the study: To assess the levels of fear and anxiety among school-age children undergoing dental treatment. Setting: The study was conducted in Outpatient Dental Clinics at Benha Teaching Hospital. Research design: A descriptive research design was utilized to conduct the study. Sample: A purposive sample of 60 school-age children and their mothers attending at the previously mentioned setting was included. Tools: Three tools were used: Tool one: A structured interviewing questionnaire for Personal characteristics of children and their mothers. Tool two: Dental Subscale of Children's Fear Survey Schedule (CFSS-DS). Tool three: Modified Dental Anxiety Scale (MDAS). Results: It was illustrated that more than two-fifths (43.3%) of children had maximum fear and more than half of children (53.3%) had maximal anxiety. Conclusion: Many school-age children undergoing dental treatment suffer from high levels of fear and anxiety. Recommendations: The study recommended further research should be conducted to assess levels of fear and anxiety among children undergoing dental treatments and preferable nursing interventions for reducing their fears and anxieties.

Keywords: fear, anxiety, children, dental treatment

Procedia PDF Downloads 80

Authors: Yuliani Aisyah, Sri Haryani, Novi Safriani

Abstract:

Nutmeg oil is one of the essential oils that have the ability as an antibacterial so it potentially uses to inhibit the growth of undesirable microbes in food. However, the essential oil that has low solubility in water, high volatile content, and strong aroma properties is difficult to apply in to foodstuffs. Therefore, the oil-in-water nanoemulsion system was used in this research. Gelatin, lecithin and tween 80 with 10%, 20%, 30% concentrations have been examined for the preparation of nutmeg oil nanoemulsions. The physicochemical properties and stability of nutmeg oil nanoemulsion were analyzed on viscosity, creaming index, emulsifying activity, droplet size, and polydispersity index. The results showed that the type and concentration stabilizer had a significant effect on viscosity, creaming index, droplet size and polydispersity index (P ≤ 0,01). The nanoemulsions stabilized with tween 80 had the best stability because the creaming index value was 0%, the emulsifying activity value was 100%, the droplet size was small (79 nm) and the polydispersity index was low (0.10) compared to the nanoemulsions stabilized with gelatin and lecithin. In brief, Tween 80 is strongly recommended to be used for stabilizing nutmeg oil nanoemulsions.

Keywords: nanoemulsion, nutmeg oil, stabilizer, stability

Procedia PDF Downloads 152

Authors: Pablo Ignacio Hernández Arango, Niels Lindemeyer

Abstract:

Chlorine, as Sodium Hypochlorite (NaClO) solution in water, is an effective, worldwide spread, and economical substance to eliminate germs in the water. The disinfection potential of chlorine lies in its ability to degrade the outer surfaces of bacterial cells and viruses. This contribution reports the main parameters of the brine electrolysis for the production of NaClO, which is afterward used for the disinfection of water either for drinking or recreative uses. Herein, the system design was simulated, optimized, build, and tested based on titanium electrodes. The process optimization considers the whole process, from the salt (NaCl) dilution tank in order to maximize its operation time util the electrolysis itself in order to maximize the chlorine production reducing the energy and raw material (salt and water) consumption. One novel idea behind this optimization process is the modification of the flow pattern inside the electrochemical reactors. The increasing turbulence and residence time impact positively the operations figures. The operational parameters, which are defined in this study were compared and benchmarked with the parameters of actual commercial systems in order to validate the pertinency of those results.

Keywords: electrolysis, water disinfection, sodium hypochlorite, process optimization

Procedia PDF Downloads 121

Authors: Maryam Mirabediny, Tsz Tin Yu, Jun Sun, Matthew Lee, Denis M. O’Carroll, Michael J. Manefield, Björn Akermark, Biswanath Das, Naresh Kumar

Abstract:

Branched perfluorooctane sulfonic acid (PFOS) is recognized as a threatening environmental pollutant due to its high persistence and bioaccumulation in various environmental matrices as well as for its toxic effects on humans and wildlife, even at very low concentrations. This study reports the first investigation of branched PFOS defluorination catalyzed by metal phthalocyanines. The reaction conditions were optimized using the different reductants and temperatures. Cobalt phthalocyanine, when combined with Ti citrate as a reducing agent, was able to defluorinate 10.9% of technical PFOS within 8 hours. In contrast, vitamin B12 only showed 2.4% defluorination during the same period under similar conditions. The defluorination mediated by cobalt phthalocyanine and Ti citrate system corresponds to 54.5% of all branched PFOS isomers (br-PFOS isomers). Isomer-specific degradation was also investigated via high-resolution LC-orbitrap, followed by their relative rates. The difference in catalytic efficacy of various phthalocyanine complexes is rationalized by their structures and electrochemical response. Lastly, a new defluorination mechanism is proposed based on the newly detected degradation products after the phthalocyanines treatment and the previous studies.

Keywords: branched isomers, catalyst, reductive defluorination, water remediation

Procedia PDF Downloads 94

Authors: Xiaodong Gao, Pingchuan Dong, Qichao Gao

Abstract:

There has been lots of published work focused on asphaltene deposited on the smooth pipe under steady conditions, while particle deposition on the blockage wellbores under transient conditions has not been well elucidated. This work attempts to predict the deposition rate of asphaltene particles in blockage tube through CFD simulation. The Euler-Lagrange equation has been applied during the flow of crude oil and asphaltene particles. The net gravitational force, virtual mass, pressure gradient, saffman lift, and drag forces are incorporated in the simulations process. Validation of CFD simulation results is compared to the benchmark experiments from the previous literature. Furthermore, the effect of blockage location, blockage length, and blockage thickness on deposition rate are also analyzed. The simulation results indicate that the maximum deposition rate of asphaltene occurs in the blocked tube section, and the greater the deposition thickness, the greater the deposition rate. Moreover, the deposition amount and maximum deposition rate along the length of the tube have the same trend. Results of this study are in the ability to better understand the deposition of asphaltene particles in production and help achieve to deal with the asphaltene challenges.

Keywords: asphaltene deposition rate, blockage length, blockage thickness, blockage diameter, transient condition

Procedia PDF Downloads 193